Compression Wood programme objectives

Overall objective

The overall objective of the project was to obtain along-term improvement in the quality of softwood timber products in terms of mechanical properties (strength and stiffness) and geometrical stability (warp, distortion) related to the occurrence of compression wood.

The general effects of compression wood on the performance of sawn timber are reduction in the strength, stiffness and dimensional stability, resulting in a decrease in yield of high quality end products and consequent financial losses.

Species selected

Work was undertaken on Sitka spruce, Norway spruce, Scots pine and European larch. These are commercially important conifer species throughout Europe and will be used to develop methodologies appropriate to other conifer species. The growth patterns of spruce, pine and larch are very different, as a result of which the formation and presentation of compression wood varies among these species.

By working on different species, common characteristics in compression wood formation and behaviour can be identified and knowledge obtained that can be readily applied to other conifers.

Specific objectives

Specifically the objectives of the project were:

  • To develop a better understanding of the formation of compression wood during growth, by considering possible cause-effect relationships between environmental constraints, silvicultural practices and individual tree growth characteristics.

  • Based on 1 to develop predictive (short-term) methodology and preventive (long-term) silvicultural strategies aimed at minimising the occurrence and the severity of compression wood in high value softwood stands.

  • To assess quantitatively the impact of compression wood on micro-structural, physical and mechanical properties.

  • To minimise the negative impact of compression wood during the various steps of processing by developing adequate processing and treatment methodologies at laboratory and industrial scale.

  • To develop new methods for identifying the presence of compression wood in saw logs and sawn timber.

  • Based on the above, to compile an overall evaluation of the impact of compression wood on the utilisation of softwood timber and suggest solutions to minimise this impact both at the silvicultural and the processing levels.

  • To incorporate the effect of compression wood into existing tree growth, yield and wood-quality models.

  • To communicate the results and conclusions to the relevant forestry and industrial sectors and seek their feedback and comments.